1 Answer

It would be important to know which phone you have, Apple has sold 4 different models of iPhones. That being said, this is a problem I have run into multiple time before on the 3G and 3GS. If you have a 3G or a 3GS then I would suggest you take a look at this guide. Specifically Step #4.

In the phone there are 3 cables that you have to plug in from the display to the board. The one which bends at a 90˚ angle, sometimes labeled "#1" is responsible for running the LCD. If this doesn't sit properly you can lose image or, as in your case, backlight.

Be sure this cable is firmly slipped into its housing. A good test is to turn the phone on while it is open, and hold that cable down with a finger.

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